Quantifying the benefits of achieving or maintaining long-term low risk profile for cardiovascular disease: The Doetinchem Cohort Study.

BACKGROUND

Studies investigating the relation between risk profiles and cardiovascular disease have measured risk at baseline only. We investigated maintenance and changes of risk profiles over time and their potential impact on incident cardiovascular disease.

DESIGN

Population-based cohort study.

METHODS

Risk factors were measured at baseline (1987-1991) among 5574 cardiovascular disease-free adults aged 20-59 years. They were classified into four risk categories according to smoking status, presence of diabetes and widely accepted cut-off values for blood pressure, total cholesterol/HDL-ratio and body mass index. Categories were subdivided (maintenance, deterioration, improvement) based on risk factor levels at six and 11 years of follow-up. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (95% CIs) for cardiovascular disease incidence 5-10 years following the risk-change period were fitted using Cox proportional hazards models.

RESULTS

Only 12% of participants were low risk at baseline, and only 7% maintained it. Participants who maintained a low risk profile over 11 years had seven times lower risk of cardiovascular disease (HR: 0.14, 95% CI: 0.05-0.41) than participants with long-term high risk profile, whereas those low risk at baseline whose profile deteriorated had three times lower risk (HR: 0.36, 95% CI: 0.18-0.71). Our results suggest that, within each baseline risk profile group, compared with a stable profile, improving profiles may be associated with up to two-fold lower HRs, and deteriorating profiles with about two-fold higher HRs.

CONCLUSIONS

Our study, using long-term risk profiles, demonstrates the full benefits of low risk profile. These findings underscore the importance of achieving and maintaining low risk from young adulthood onwards.